Why There Are Two Sexes

Please for the love of god listen to me.Your model says when a cell divides, there is an active strand and an inactive strand.From your paper: An AB phenotype is impossible using your model. Both sites must be transcribed.There is no such thing as an AB allele. Got it? There is an A and a B. They are different versions of the SAME GENE. Understand? They have the same location on the chromosome. When the two chromosomes are lined up side by side, they are right next to each other. An A on one strand, a B on the other.From your conclusion: An AB blood type is impossible.

Every cell in your body is a diploid cell!Diploid: having two copies of each chromosome. A full set of genetic material, consisting of paired chromosomes one chromosome from each parental set. Haploid: having only one copy of each chromosome.The only haploid cells in your body are gametes (eggs/sperm). This does not happen.You know why it's important to get the correct blood type in a transfusion, right?Because if you get A or B when you are AB, it can kill you.You are suggesting that one person expresses multiple blood types.Wrong wrong wrong wrong wrong. You do not understand what a chromosome is.Every cell has 46 chromosomes. 23 pairs.This is a chromosome pair. Here is a single chromosome on the left, a chromosome pair on the right. Here is a closer view. As you can see, one arm contains 2 strands of DNA.These are the 23 chromosomes in a diploid cell: Every cell in your body has a full set of these.Here is a picture of the location of the ABO gene (the red line) on chromosome 9: You get one copy of the ABO gene from Mom and one copy from Dad.Now. Let's apply this to the AB blood type.If Mom is type A, she can have two genotypes: AA, AO
If Dad is type B, he can have two genotypes: BB, BO
If you are type AB, you got an A from Mom and a B from Dad.
That means that one arm of chromosome 9 has A and one arm of chromosome 9 has B.Now. Let's discuss the nature of a gene.A gene is a specific genomic sequence on one strand of DNA. Since DNA is complementary, the other strand has the same sequence, in reverse order (DNA strands run anti-parallel).That means that one arm of chromosome 9 has two copies of the A gene, one on each strand, and the other arm has two copies of the B gene, one on each strand.When a cell divides, both strands replicate.Both strands are functional.The only known exception to this rule in X chromosome inactivation.Gene suppression does occur, at the level of transcription or translation. But entire strand suppression does not.Edited by molbiogirl, : No reason given.Edited by molbiogirl, : added picEdited by molbiogirl, : clarity and more pics

My bad. I should have said chromosome, not strand.

M, I give up.Since you can't see that a person who produced those 4 blood types WOULD BE DEAD, I can't help you.